Aluminum grain refiner containing duplex crystals

摘要

Disclosed is a new aluminum grain refiner alloy with a controlled, effective content of "duplex" crystals. The duplex crystals are made by (1) producing aluminides that contain boron in solution, and by (2) aging said aluminide in a manner to precipitate at least part of the boron to form the duplex crystals. The duplex crystals have been discovered to be extremely potent grain refining agents.